/** * HTTP status failure with payload details. */export class HttpStatus extends Error {  public readonly status: number;  public readonly detail: string;   /**   * Create an HTTP status error.   * @param status - HTTP status code.   * @param detail - Error detail message.   */  public constructor(status: number, detail: string) {    super(detail);    this.status = status;    this.detail = detail;  }} /** * Check whether a value is an HttpStatus instance. * @param value - Unknown error value. * @returns True if value is HttpStatus. */export const isHttpStatus = (value: unknown): value is HttpStatus =>  value instanceof HttpStatus; /** * Create a not-found HttpStatus error. * @param detail - Error detail message. * @returns HttpStatus instance. */export const notFound = (detail: string): HttpStatus => new HttpStatus(404, detail); /** * Create a bad-request HttpStatus error. * @param detail - Error detail message. * @returns HttpStatus instance. */export const badRequest = (detail: string): HttpStatus => new HttpStatus(400, detail); /** * Create a service-unavailable HttpStatus error. * @param detail - Error detail message. * @returns HttpStatus instance. */export const serviceUnavailable = (detail: string): HttpStatus => new HttpStatus(503, detail);